The difference is we don't live in the sky. As long as there isn't noise pollution (and electric planes are supposedly a lot quieter), you have to try really hard to create and issue here. Aviation is getting ever more automated and safer.
Planes will not be a solution for all transportation needs, but where it makes sense they're great. A flying bus basically, routes can be very flexibly changed depending on evolving needs.
Public transport is factors more efficient than air travel.
And yes including initial cost.
We build infrastructure to last not to throw it away 5 years later.
You need to understand how much more energy it actually costs to bring a plain up in the air and down again. We talk magnitude more energy than trains.
We can talk about this again in 20 years when solid state batteries are broken through.and sustainable energy sources are the norm.
Air taxi's ate not hard to build on a technical level. We know how to build them.